Power seats not working / Mufflers creating too much roar/vibration

I have 2 things to inguire about:
1.  The power seats in my 94 stopped working.  Fuse and circuit breaker are OK.  The circuit breaker heats up - not a good thing.  They were working one day and not the next.  I can't figure it out???  Maybe a ground short somewhere, but I don't know where to start looking.  Any ideas?

2. I had Flowmaster mufflers installed.  They sound great outside of the car, but they create a very annoying roar/vibration/pressure inside the cabin.  Rather than going back to original equipment mufflers, can anyone recommend something (at a reasonable cost - not on of those high dollar complete exhaust systems)?

Thanks,
Gene.  

Gene, I have a very similar problem with my exhaust on an 89 L98. I put on mufflers that were supposed to be OEM replacements, and the cat back pipe with the crossover, and the interior roar is really annoying, particularly at low speed. Have you come up with any solution?
Jerry